Whilst certainly a legal tackle i believed it crossed the line morally.
As i recalled it Edwards was 5 metres behind Hayne as Hayne, with his back facing edwards, raised his hand calling for the ball from a teammate about to be tackled with it on the last. Edwards, seeing Hayne raise his hand, quickly lowers his head and charges at Hayne with the intention to drive his shoulder into Haynes lower back. Keep in mind Edwards is now driving with no possible vision to know which way Hayne is facing or if he even received the ball.
The only thing that stopped it from been a full blown dog shoulder charge into Hyanes spine or kidneys was the fact that Hayne turned at the last second to attempt a quick catch and pass. Edwards hits hayne the very millisecond the ball touches his hand - don't try and tell me Edwards is Will Hunting in mathematical ability and calculated a bunch of stuff allowing him to blindly hit Hayne the millisecond he touched the ball.
Edwards greatest, probably forever, career highlight is a dog shot that most players wouldn't feel necessary to do through fear of seriously injuring the opposing player.